JP2009174632A - Vehicle control device, control method, program for realizing its method by computer and recording medium for recording its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately control a clutch in creep travel. <P>SOLUTION: An ECU executes a program including a step (S110) of setting a target value by adding a predetermined value to a present position when there is no variation in an operation quantity of a clutch actuator (NO in S108) when there is a variation in a rotating speed difference between an engine speed and an input shaft rotating speed of a transmission (YES in S104) after a prerequisite has been established (S100), a step (S112) of controlling the clutch actuator so that the operation quantity becomes the target value, a step (S118) of setting the present position to the target value when the variation in the rotating speed difference is eliminated (NO in S116), and a step (S122) of returning the target value to an initial value when the clutch is put into an engaging state (YES in S120). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to control of a vehicle in which a clutch operated by an actuator is provided between an engine and a transmission, and more particularly to control of a clutch during execution of creep control.

  Conventionally, automatic control that is provided between an engine and a transmission and that is operated by hydraulic pressure is operated by an actuator or the like. In a vehicle provided with such a clutch, the clutch is controlled to be in a half-engaged state in order to develop a driving force similar to the creep force of the automatic transmission when the vehicle starts.

  As a vehicle provided with such a clutch, for example, Japanese Patent Laid-Open No. 2002-31166 (Patent Document 1) secures a constant creep force while preventing vibration and noise from being generated by control hunting during creep. Disclosed is an automatic clutch control device capable of reliably performing a creep operation. The automatic clutch control device detects engine rotation state detection means for detecting the engine rotation state, clutch stroke detection means for detecting the clutch stroke, clutch actuator for connecting / disconnecting the clutch, and engine rotation state detection means. Based on the engine rotation state and the clutch stroke detected from the clutch stroke detecting means, the creep point at which the vehicle starts creeping is detected, and when it is determined that the creep point has been reached, the clutch actuator is maintained so as to maintain the clutch stroke. And a control means for controlling.

According to the automatic clutch control device disclosed in the above publication, there is an advantage that vibration and noise can be prevented from being generated by control hunting during the creep operation.
JP 2002-31166 A

  However, when creep running is carried out continuously or intermittently, there is a problem that frictional heat is generated at the engaging portion of the clutch due to the longer period of half-engagement of the clutch. . When the temperature of the engaging portion becomes high due to heat generation, the temperature of the components of the clutch increases, and the temperature of the hydraulic oil in the hydraulic circuit connected to the clutch may increase. For example, when the hydraulic circuit is closed by being shut off from a reservoir or the like, the volume expands when the temperature of the hydraulic oil in the hydraulic circuit rises, so that the hydraulic pressure in the hydraulic circuit increases. Therefore, the clutch may be operated to the disengagement side even though the actuator is operated so as to continue the half-engaged state of the clutch. As a result, there is a possibility that creep running cannot be continued.

  In the automatic clutch control device disclosed in the above-mentioned publication, the clutch is controlled based on the output value of the clutch stroke sensor. However, since no consideration is given to the change in hydraulic pressure due to the volume expansion of the hydraulic oil, creep travel is performed. The problem of the clutch being released cannot be solved.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vehicle control device, a control method, and a program for realizing the method by a computer that accurately control the clutch during creep running. And a recording medium on which the program is recorded.

  According to a first aspect of the present invention, there is provided a vehicle control apparatus including: an internal combustion engine; a clutch that is connected to an output shaft of the internal combustion engine and operates to connect / disconnect power transmission by hydraulic pressure; A transmission control device for a vehicle on which a transmission is mounted. The clutch is operated by driving an actuator. The actuator is controlled so that the clutch is in a predetermined half-engaged state when a predetermined condition for the state of the vehicle is satisfied. In this control device, means for detecting the operation amount of the actuator, means for detecting the rotational speed of the internal combustion engine, means for detecting the rotational speed of the input shaft of the transmission, and a clutch are predetermined. After the actuator is controlled to be in a half-engaged state, the rotational speed difference between the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission fluctuates and the detected operation And a control means for controlling the actuator so that the clutch operates to the engagement side when the amount does not change. The vehicle control method according to the eighth invention has the same configuration as the vehicle control device according to the first invention.

  According to the first invention, when a predetermined condition is satisfied, the control is started so that the clutch is in a predetermined half-engagement state, and the creep running of the vehicle is realized. After the actuator is controlled so that the clutch is in a predetermined half-engaged state, if the clutch is operated to the disengagement side due to an increase in hydraulic pressure due to the volume expansion of the hydraulic oil, the operating amount of the actuator varies. In spite of no state, there is a state where the rotational speed difference between the internal combustion engine and the rotational speed of the input shaft of the transmission fluctuates. In such a case, the half-engaged state of the clutch can be continued by controlling the actuator so that the clutch operates to the engagement side. Thereby, creep driving | running | working can be implemented appropriately. Therefore, it is possible to provide a vehicle control apparatus and control method for accurately controlling the clutch during creep running.

  In the vehicle control apparatus according to the second aspect of the invention, in addition to the configuration of the first aspect, the control means provides an operation amount that has changed from the detected operation amount to the clutch engagement side by a predetermined value. Setting means for setting as a target value and means for controlling the actuator so that the detected operation amount becomes the set target value are included. A vehicle control method according to a ninth aspect has the same configuration as the vehicle control apparatus according to the second aspect.

  According to the second aspect of the invention, by setting the operation amount that has changed from the detected operation amount to the engagement side of the clutch by a predetermined value as a target value and controlling the actuator, The clutch that has been operating on the disengagement side can be brought into the half-engaged state again. Therefore, creep running can be performed appropriately.

  According to a third aspect of the present invention, in the vehicle control apparatus, in addition to the second aspect, the setting means sets the target value once changed to the half-engaged state when a predetermined condition is not satisfied. Means for setting to a corresponding predetermined value. A vehicle control method according to a tenth invention has the same configuration as the vehicle control device according to the third invention.

  According to the third invention, when the clutch is engaged or disengaged, the generation of frictional heat is suppressed, so that the temperature of the hydraulic oil is lowered and the expanded volume is reduced. Therefore, if the predetermined condition is not satisfied, the target value once changed is set to a predetermined value corresponding to the half-engaged state, so that the predetermined condition is satisfied again and the clutch is After the control of the actuator is started so as to be in the half-engaged state, the clutch can be brought into the half-engaged state with high accuracy. As a result, the creep running can be appropriately performed.

  In addition to the configuration of any one of the first to third inventions, the vehicle control device according to the fourth invention holds the operating amount of the actuator when the rotational speed difference does not fluctuate due to the control of the actuator by the control means. Means for further including. A vehicle control method according to an eleventh invention has the same configuration as the vehicle control device according to the fourth invention.

  According to the fourth aspect of the invention, when the clutch returns to the half-engaged state, the rotational speed difference does not fluctuate, so that the half-engaged state of the clutch can be continued by maintaining the operation amount of the actuator. . Therefore, creep running can be performed appropriately.

  In the vehicle control device according to the fifth invention, in addition to the configuration of any one of the first to fourth inventions, the predetermined condition is that the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission are This includes a condition that the vehicle does not fluctuate and a condition that an accelerator pedal and a brake pedal provided on the vehicle are released. A vehicle control method according to a twelfth aspect of the invention has the same configuration as the vehicle control apparatus according to the fifth aspect of the invention.

  According to the fifth aspect of the present invention, the clutch is half-engaged when the condition that the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission do not fluctuate and the condition that the depression of the accelerator pedal and the brake pedal are released are satisfied. By setting the state, it is possible to appropriately perform creep running.

  The vehicle control device according to a sixth aspect of the present invention is that, in addition to the configuration of any one of the first to fifth aspects, the detected rotational speed difference is equal to or greater than a predetermined first value. And means for determining that the detected operation amount does not change if the detected change amount of the operation amount is equal to or less than a predetermined second value. Further included. A vehicle control method according to a thirteenth aspect has the same configuration as the vehicle control apparatus according to the sixth aspect.

  According to the sixth aspect of the present invention, it can be accurately determined that the rotational speed difference is fluctuating when the rotational speed difference is equal to or greater than a predetermined first value. Furthermore, if the detected change amount of the operation amount is equal to or less than a predetermined second value, it can be accurately determined that the operation amount of the actuator does not vary.

  In the vehicle control apparatus according to the seventh aspect of the invention, in addition to the configuration of any one of the first to sixth aspects, a clutch release cylinder is connected to the clutch via a hydraulic circuit. The clutch release cylinder supplies hydraulic pressure to the clutch via a hydraulic circuit by moving a piston slidably provided therein by driving of an actuator. The clutch release cylinder is connected to a reservoir for storing hydraulic oil supplied into the hydraulic circuit via a reserve port. The reserve port and the hydraulic circuit are cut off when the piston is in a position where the clutch is released from a position corresponding to a predetermined half-engaged state. A vehicle control method according to a fourteenth aspect of the invention has the same configuration as the vehicle control device according to the seventh aspect of the invention.

  According to the seventh aspect of the present invention, when the clutch is in the half-engaged state, when the hydraulic circuit and the reservoir are disconnected, the hydraulic circuit is closed. The frictional heat generated expands the volume, and as a result, the clutch may be released. Therefore, by controlling the actuator so that the clutch operates to the engagement side, the half-engaged state of the clutch can be continued, so that the creep travel can be appropriately performed.

  A program according to a fifteenth invention is a program for realizing the vehicle control method according to any of the eighth to fourteenth inventions by a computer, and the recording medium according to the sixteenth invention is the eighth to fourteenth invention. A medium having recorded thereon a computer-implemented method for controlling a vehicle according to any one of the inventions.

  According to the fifteenth or sixteenth invention, the vehicle control method according to any of the eighth to fourteenth inventions can be realized using a computer (which may be general purpose or dedicated).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 1, a vehicle equipped with a vehicle control device according to the present embodiment will be described. The vehicle includes an internal combustion engine (hereinafter referred to as an engine) 200, a clutch 300, a transmission 400, a clutch actuator 500, and an ECU 100 (Electronic Control Unit).

  The vehicle travels by the driving force generated by the engine 200 being transmitted to the clutch 300 and the transmission 400 and finally being transmitted to driving wheels (not shown). The operations of engine 200, transmission 400, and clutch actuator 500 are controlled by ECU 100. The vehicle control apparatus according to the present embodiment is expressed by a program executed in ECU 100, for example.

  The engine 200 is a gasoline engine. A diesel engine may be used instead of the gasoline engine. Clutch 300 is coupled to crankshaft 202 that is the output shaft of engine 200. The output shaft 308 of the clutch 300 is connected to the input shaft of the transmission 400.

  The transmission 400 is composed of a constantly meshing gear train. Note that the transmission 400 is not particularly limited to a transmission including a constantly meshing gear train. Further, in the present embodiment, it is assumed that the gear stage selection in transmission 400 is performed by sliding the shift fork shaft by the operation of the shift actuator based on the driver's operation instruction or the traveling state of the vehicle. However, it is not particularly limited to this. The shift actuator may be operated by hydraulic pressure or may be operated by electric power. Note that the gear stage may be selected by a shift actuator using a direct cylinder.

  Clutch 300 is connected to clutch release cylinder 450 via hydraulic circuit 452. A piston 454 is slidably provided in the clutch release cylinder 450. Piston 454 is coupled to one end of release shaft 456, and the other end of release shaft 456 is connected to clutch actuator 500.

  In the present embodiment, clutch actuator 500 includes an electric motor, a speed reduction mechanism, and a return spring (all not shown). The other end of the release shaft 456 is connected to an electric motor via a speed reduction mechanism. Note that the other end of the release shaft 456 may be directly connected to the electric motor.

  The reduction mechanism is composed of a plurality of gears and reduces the rotation of the electric motor. The speed reduction mechanism converts the movement of the electric motor in the rotational direction into the movement of the release shaft 456 in the axial direction (left and right direction in FIG. 1). Therefore, when the electric motor operates, the release shaft 456 moves in the axial direction. For example, when the release shaft 456 is moved leftward in FIG. 1 by the electric motor, the piston of the clutch release cylinder 450 is moved leftward in FIG. The hydraulic circuit 452 is filled with hydraulic oil, and the hydraulic pressure in the hydraulic circuit 452 increases as the piston moves.

  The return spring is provided so that an urging force is generated in a direction to return the position of the release shaft to the initial value when moved in the axial direction from the initial position of the release shaft 456 by the operation of the electric motor. Therefore, when the power supply to the electric motor is stopped, the release shaft 456 is moved to the initial position by the biasing force of the return spring. The hydraulic pressure in the hydraulic circuit 452 decreases due to the movement of the release shaft 456 to the initial position.

  The clutch actuator 500 is provided with a clutch stroke sensor 502 that detects a physical quantity related to the operation amount of the clutch actuator 500. The detection target of the clutch stroke sensor 502 is not particularly limited as long as a physical quantity related to the operation amount of the clutch actuator 500 is detected. For example, the clutch stroke sensor 502 is a movement amount of the release shaft 456, a deceleration rate. Either the rotation amount of the gear of the mechanism or the rotation amount of the electric motor may be detected as the operation amount of the clutch actuator 500. In this embodiment, the “operation amount of the clutch actuator 500” indicates the operation amount starting from the initial position, and the operation amount detected by the clutch stroke sensor 500 is the release shaft 456, the gear of the speed reduction mechanism. Or the present position from the initial position of the electric motor is shown. The initial position may be a position where the clutch 300 is engaged or a position where the clutch 300 is released.

  The clutch release cylinder 450 is connected to a reservoir (not shown) for storing hydraulic oil supplied into the hydraulic circuit 452 via a reserve port (not shown). The reserve port is connected to the clutch release so that the reserve port and the hydraulic circuit 452 are disconnected at a position where the piston 300 is released from a position corresponding to the predetermined half-engaged state of the clutch 300. A hydraulic circuit 452 is provided in the cylinder 450 and connected to the clutch release cylinder 450.

  The clutch 300 has a flywheel 302 connected to the crankshaft 202, a rotary disc that is the same as the flywheel 302, a clutch disc 304 that is connected to the input shaft of the transmission 400, and a contact with the clutch disc 304. And a pressure plate (not shown) provided on the clutch cover 306, and the pressure plate is pressed against the clutch disc 304 side by the urging force generated based on the shape and material, or the release mechanism (not shown) is operated. It is composed of a diaphragm spring that is separated from the pressure plate.

  The hydraulic pressure supplied from the clutch release cylinder 450 via the hydraulic circuit 452 is supplied to the release mechanism of the clutch 300. The release mechanism operates so as to weaken the force by which the diaphragm spring presses the pressure plate against the flywheel 302 in response to an increase in the hydraulic pressure supplied from the hydraulic circuit 452, and the diaphragm spring acts on the pressure plate by the biasing force in response to a decrease in hydraulic pressure. Is a mechanism that operates so as to increase the force of pressing the flywheel 302 against the flywheel 302. Such a mechanism may use a well-known technique and will not be described in detail.

  When the force that presses the pusher plate against the flywheel 302 is weakened, the degree of engagement between the flywheel 302 and the clutch disc 304 is reduced, so that the clutch 300 is operated to be in a released state.

  On the other hand, when the force pressing the pressure plate against the flywheel 302 is increased, the degree of engagement between the flywheel 302 and the clutch disk increases, so that the clutch 300 operates to be in an engaged state.

  In the present embodiment, the “disengaged state” of the clutch 300 refers to a state in which power is not transmitted between the flywheel 302 and the clutch disc 304. The “engaged state” refers to a state in which the flywheel 302 and the clutch disc 304 rotate together. The “half-engaged state” refers to a state in which the flywheel 302 and the clutch disc 304 rotate while causing slip (that is, a rotational difference).

  The ECU 100 is connected to a stop lamp switch 102, an accelerator opening sensor 104, an input shaft rotational speed sensor 106, an engine rotational speed sensor 108, and a clutch stroke sensor 502.

  The stop lamp switch 102 is a switch provided on the brake pedal 150, and is turned on when the amount of depression of the brake pedal 150 exceeds a predetermined amount, and is turned off when the amount is smaller than the predetermined amount. The stop lamp switch 102 transmits an ON signal to the ECU 100. In the present embodiment, it is only necessary to detect a physical quantity indicating whether or not the depression of the brake pedal 150 has been released. For example, the stroke quantity (depression quantity) of the brake pedal 150 is detected instead of the stop lamp switch 102. A stroke sensor may be used.

  The accelerator opening sensor 104 detects the depression amount of the accelerator pedal 152, that is, the accelerator opening. The accelerator opening sensor 104 transmits a signal indicating the detected accelerator opening to the ECU 100.

  Input shaft rotational speed sensor 106 detects the rotational speed of the input shaft of transmission 400. Input shaft rotational speed sensor 106 transmits to ECU 100 a signal indicating the detected rotational speed of the input shaft of transmission 400.

  The engine speed sensor 108 detects the speed of the crankshaft 202. The engine speed sensor 108 transmits a signal indicating the detected speed of the engine 200 to the ECU 100.

  The clutch stroke sensor 502 detects the operation amount of the clutch actuator 500. Clutch stroke sensor 502 transmits a signal indicating the detected operation amount to ECU 100.

  ECU 100 performs arithmetic processing based on signals transmitted from these sensors, programs and maps stored in a memory (not shown), and the like. Thereby, the ECU 100 controls the clutch 300. ECU 100 may control the output of engine 200 and the speed change operation of transmission 400 along with control of clutch 300.

  In the configuration of the vehicle as described above, when a predetermined condition for starting creep control is established for the vehicle state, the ECU 100 causes the clutch actuator 500 to be in a predetermined half-engaged state. Start control. As a result, the vehicle starts creep control. In the present embodiment, “creep control” refers to control that realizes a driving force similar to the creep force generated in the automatic transmission by controlling the clutch 300.

  The predetermined condition includes at least a condition that the engine speed and the input shaft speed do not fluctuate and a condition that the accelerator pedal 152 and the brake pedal 150 provided in the vehicle are released. Additional conditions regarding the traveling state (for example, the vehicle speed is within a predetermined range) or the engine state (for example, the engine speed is equal to or higher than the predetermined speed) may be included.

  For example, when the vehicle is stopped and both the brake pedal 150 and the accelerator pedal 152 are released, the ECU 100 determines that a predetermined condition is satisfied, and uses the clutch stroke sensor 502. The clutch actuator 500 is controlled so that the detected operation amount of the clutch actuator 500 becomes a predetermined operation amount corresponding to the half-engaged state. As a result, the flywheel 302 and the clutch disc 304 are in a semi-engaged state.

  At this time, the force with which the diaphragm spring presses the pressure plate is smaller than that in the engaged state. Therefore, when the driving load on the clutch disk 304 side is high, such as when the vehicle is stopped, the flywheel 302 and the clutch disk It rotates with 304, producing a slip.

  As a result, when the vehicle starts, the power can be transmitted without causing the engine 200 to stall, and the vehicle starts to travel with the transmitted power. When the vehicle starts traveling, the slip amount decreases as the rotational speed of the input shaft of the transmission 400 increases. Unless both the brake pedal 150 and the accelerator pedal 152 are depressed, the rotational speed of the engine 200 and the rotational speed of the input shaft of the transmission 400 are finally substantially the same.

  In such a vehicle, when creep control is carried out continuously or intermittently, the clutch 300 is a flywheel that is an engaging portion of the clutch 300 due to a longer period during which the clutch 300 is in a semi-engaged state. Frictional heat may occur between 302 and the clutch disk 304.

  When the temperature of the engaging portion becomes high due to frictional heat, the temperature of the components of the clutch 300 increases, and the temperature of the hydraulic oil in the hydraulic circuit 452 increases. When the temperature of the hydraulic oil in the hydraulic circuit 452 rises, the volume expands. Therefore, when the hydraulic circuit 452 and the reservoir are shut off during creep control, the hydraulic oil cannot be released via the reserve port, and adjustment of the amount of fluid in the hydraulic circuit 452 by the reservoir is not possible. Therefore, the hydraulic pressure in the hydraulic circuit 452 increases. Therefore, the clutch 300 may be operated to the disengagement side even though the clutch actuator 500 is operated so as to continue the half-engagement state of the clutch 300. As a result, there is a possibility that the vehicle cannot continue to travel by creep control.

  Therefore, in the present invention, after the ECU 100 controls the clutch actuator 500 so that the clutch 300 is in a predetermined half-engaged state, the rotational speed of the engine 200 and the rotational speed of the input shaft of the transmission 400 are determined. The clutch actuator 500 is controlled such that the clutch 300 is operated to the engagement side when the rotational speed difference fluctuates and the operation amount of the clutch actuator 500 does not fluctuate.

  Specifically, the ECU 100 determines whether or not the clutch actuator 500 is controlled so that the clutch 300 is in a predetermined half-engaged state, indicating in advance that the vehicle is creeping. Judgment is made based on whether or not the preconditions established are satisfied. In the present embodiment, the “predetermined precondition” is, for example, that both the engine speed and the rotation speed of the input shaft of the transmission 400 are constant (that is, the amount of change is equal to or less than a predetermined value). And the condition that any depression of the brake pedal 150 and the accelerator pedal 152 is released.

  Further, ECU 100 indicates that the rotational speed difference fluctuates if the rotational speed difference between the rotational speed of engine 200 and the rotational speed of the input shaft of transmission 400 is equal to or greater than a predetermined value (1). judge. ECU 100 is in a state where the rotational speed difference fluctuates during creep control if the amount of change in the rotational speed difference between engine speed and input shaft speed of transmission 400 is equal to or greater than a predetermined value. You may make it determine that it is.

  Further, ECU 100 determines that the operation amount of clutch actuator 500 does not vary when the change amount of the operation amount of clutch actuator 500 is equal to or less than a predetermined value (2).

  ECU 100 may calculate the amount of change based on the difference between the value at the previous calculation cycle and the value at the current calculation cycle, or may calculate the amount of change during a predetermined period. Also good.

  ECU 100 changes the rotational speed difference between the rotational speed of engine 200 and the rotational speed of the input shaft of transmission 400 after clutch actuator 500 is controlled so that clutch 300 is in a predetermined half-engaged state. In this state, when the operation amount of the clutch actuator 500 does not change, the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 is changed to the engagement side of the clutch 300 by a predetermined value. Set the operating amount to the target value. The ECU 100 controls the clutch actuator 500 so that the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 becomes a set target value.

  Further, ECU 100 retains the operation amount of clutch actuator 500 when the difference between the rotational speed of engine 200 and the rotational speed of the input shaft of transmission 400 does not vary under the control of clutch actuator 500.

  Further, ECU 100 sets the operation amount of clutch actuator 500 corresponding to the half-engaged state as a target value when a predetermined condition is not satisfied.

  FIG. 2 shows a functional block diagram of ECU 100 that is the vehicle control apparatus according to the present embodiment. ECU 100 includes an input interface (hereinafter referred to as an input I / F) 600, an arithmetic processing unit 700, a storage unit 800, and an output interface (hereinafter referred to as an output I / F) 900.

  The input I / F 600 includes a stop lamp switch signal from the stop lamp switch 102, an accelerator opening signal from the accelerator opening sensor 104, an input shaft speed signal from the input shaft speed sensor 106 of the transmission 400, The engine speed signal from the engine speed sensor 108 and the clutch stroke signal from the clutch stroke sensor 502 are received and transmitted to the arithmetic processing unit 700.

  Arithmetic processing unit 700 includes a condition establishment determination unit 702, a rotation speed difference variation determination unit 704, a position variation determination unit 706, a target value setting unit 708, an actuator control unit 710, and an engagement determination unit 712. .

  The condition establishment determination unit 702 determines whether a predetermined precondition is satisfied. “Predetermined precondition” is a condition indicating that the vehicle is creeping. Predetermined conditions are, for example, a condition that both the engine speed and the speed of the input shaft of the transmission 400 are constant (that is, the amount of change is equal to or less than a predetermined value), and the brake pedal 150 and the accelerator pedal. And the condition that any of the steps 152 is released. Note that the condition satisfaction determination unit may turn on a condition satisfaction determination flag when a predetermined precondition is satisfied, for example.

  Note that the condition satisfaction determination unit 702 may turn on a condition satisfaction determination flag when it is determined that a predetermined condition is satisfied, for example.

  If it is determined that the engine speed varies after a predetermined precondition is satisfied, the rotational speed difference variation determination unit 704 determines the rotational speed difference between the engine rotational speed and the input shaft rotational speed of the transmission 400. Determine if there is any fluctuation. Specifically, the rotational speed difference variation determination unit 704 determines that there is a variation in the rotational speed difference when the rotational speed difference is equal to or greater than a predetermined value (1).

  The rotational speed difference variation determining unit 704 determines, for example, whether or not there is a variation in the rotational speed difference when the condition satisfaction determination flag is on, and determines that there is a variation in the rotational speed difference. The determination flag may be turned on.

  When it is determined that there is a change in the rotational speed difference, the position change determination unit 706 determines whether there is a change in the operation amount of the clutch actuator 500. Specifically, the position variation determination unit 706 determines that there is no variation in the operation amount of the clutch actuator 500 when the change amount of the operation amount of the clutch actuator 500 is equal to or less than a predetermined value (2). For example, if the rotational speed difference variation determination flag is on, the position variation determination unit 706 determines whether or not the operation amount of the clutch actuator 500 varies, and if there is no variation in the operation amount of the clutch actuator 500, The fluctuation determination flag may be turned on.

  The target value setting unit 708 satisfies a predetermined precondition, changes in the rotational speed difference between the engine speed and the speed of the input shaft of the transmission 400, and does not change the operating amount of the clutch actuator 500. Then, the operation amount changed from the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 to the engagement side of the clutch 300 by a predetermined value is set as a target value. In the present embodiment, in the operation amount of the clutch actuator 500, the change on the engagement side of the clutch 300 is defined as a positive direction. Therefore, the target value setting unit 708 sets a value obtained by adding a predetermined value to the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 as a target value.

  Note that the target value setting unit 708 may set the target value when, for example, the condition satisfaction determination flag, the rotation speed difference variation determination flag, and the position variation determination flag are all on.

  Further, the target value setting unit 708 determines the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 when the rotational speed difference between the rotational speed of the engine 200 and the rotational speed of the input shaft of the transmission 400 does not fluctuate. Set as target value. In the present embodiment, for example, target value setting unit 708 detects by clutch stroke sensor 502 when the rotational speed difference between the rotational speed of engine 200 and the input shaft rotational speed of transmission 400 is equal to or smaller than a predetermined value. The actuated amount of the clutch actuator 500 is set as a target value.

  Furthermore, when a predetermined condition for starting creep control is not satisfied (for example, when clutch 300 is engaged), target value setting unit 708 changes the target value once changed to a semi-engaged state. A corresponding predetermined value is set. This is because the clutch 300 is accurately brought into the half-engaged state after the predetermined condition is satisfied again and the control of the clutch actuator 500 is started so that the clutch 300 is brought into the half-engaged state.

  The actuator control unit 710 controls the clutch actuator 500 so that the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502 becomes a set target value. The actuator control unit 710 generates a clutch actuator control signal based on the set target value, and transmits the clutch actuator control signal to the clutch actuator 500 via the output I / F 900.

  The engagement determination unit 712 determines whether or not the clutch 300 is in an engaged state. For example, the engagement determination unit 712 determines whether or not the clutch 300 is engaged based on the operation amount of the clutch actuator 500 detected by the clutch stroke sensor 502.

  In this embodiment, the condition establishment determination unit 702, the rotation speed difference variation determination unit 704, the position variation determination unit 706, the target value setting unit 708, the actuator control unit 710, and the engagement determination unit 712 are all subjected to arithmetic processing. The description will be made assuming that a CPU (Central Processing Unit), which is the unit 700, functions as software, which is realized by executing a program stored in the storage unit 800, but may be realized by hardware. Such a program is recorded on a recording medium and mounted on the vehicle.

  Various information, programs, threshold values, maps, and the like are stored in the storage unit 800, and are read from the arithmetic processing unit 700 as necessary.

  Hereinafter, with reference to FIG. 3, a control structure of a program executed by ECU 100 that is the control device for the vehicle according to the present embodiment will be described.

  In step (hereinafter, step is referred to as S) 100, ECU 100 determines whether or not a predetermined precondition is satisfied. If a predetermined precondition is satisfied (YES in S100), the process proceeds to S102. If not (NO in S100), the process returns to S100.

  In S102, ECU 100 calculates a rotational speed difference between the engine rotational speed and the input shaft rotational speed of transmission 400. In S104, ECU 100 determines whether or not there is a change in the calculated rotational speed difference. If the rotational speed difference varies (YES in S104), the process proceeds to S106. If not (NO in S104), the process returns to S100.

  In S <b> 106, ECU 100 detects the operation amount of clutch actuator 500 by clutch stroke sensor 502. In S108, ECU 100 determines whether or not there is a change in the detected operation amount of clutch actuator 500. If there is no change in the operation amount of clutch actuator 500 (NO in S108), the process proceeds to S110. If not (YES in S108), the process returns to S100.

  In S110, ECU 100 sets a value obtained by adding a predetermined value to the operation amount of clutch actuator 500 detected by clutch stroke sensor 502 as a target value. In S112, ECU 100 controls clutch actuator 500 so that the operation amount of clutch actuator 500 detected by clutch stroke sensor 502 becomes a set target value. In S114, ECU 100 calculates a rotational speed difference between the engine rotational speed and the input shaft rotational speed of transmission 400.

  In S116, ECU 100 determines whether or not the rotational speed difference is equal to or greater than a predetermined value (1). If the rotational speed difference is equal to or greater than a predetermined value (1) (YES in S116), the process returns to S110. If not (NO in S116), the process proceeds to S118.

  In S118, ECU 100 sets the operation amount of clutch actuator 500 detected by clutch stroke sensor 502 as a target value. In S120, ECU 100 determines whether or not clutch 300 is in an engaged state. When the clutch is engaged (YES in S120), the process proceeds to S122. If not (NO in S120), the process returns to S100. In S122, ECU 100 returns the target value to a predetermined operation amount corresponding to the half-engaged state of clutch 300, which is the initial value.

  An operation of ECU 100 as the vehicle control apparatus according to the present embodiment based on the structure and flowchart as described above will be described with reference to FIG.

  For example, it is assumed that the engine 200 is being started and the driver has stepped on the brake pedal to stop the vehicle. Since the driver depresses the brake pedal 150, the stop lamp switch 102 is in an on state. Further, in a state where the accelerator pedal 152 is released, the engine speed is controlled so as to be an idle speed set according to the state of the engine 200. Further, it is assumed that the clutch actuator 500 is controlled so that the clutch 300 is in a released state. At this time, since the vehicle is stopped, the rotational speed of the input shaft of the transmission 400 is substantially zero.

  When the driver releases the depression of the brake pedal 150 at time T (0), the stop lamp switch 102 is turned off. At this time, creep control is executed because a predetermined condition is satisfied. Therefore, the clutch actuator 500 operates to have a predetermined operation amount corresponding to the half-engaged state of the clutch 300.

  When the engagement of the flywheel 302 and the clutch disc 304 of the clutch 300 is started by the operation of the clutch actuator 500, the power of the engine 200 is transmitted to the drive wheels, so the rotational speed of the input shaft of the transmission 400 is determined by the degree of engagement. It rises according to the rise of. As the rotational speed of the input shaft of the transmission 400 increases, the vehicle speed increases and the vehicle starts running.

  When the slip amount decreases as the vehicle speed increases, at the time T (1), the rotational speed difference between the engine rotational speed and the input shaft rotational speed of the transmission 400 becomes substantially zero. After time T (1), the engine speed and the input shaft speed of the transmission 400 are substantially constant. Therefore, since a predetermined precondition is satisfied (YES in S100), the rotational speed difference between the engine rotational speed and the input shaft rotational speed of the transmission is calculated (S102). From time T (1) to time T (2), since the rotational speed difference is in a constant state (NO in S104), creep control is continuously performed.

  At time T (2), when the temperature of the hydraulic oil in the hydraulic circuit 452 rises due to frictional heat generated between the flywheel 302 and the clutch disc 304 and the volume expands, the hydraulic pressure supplied to the release mechanism increases. Thus, the clutch 300 is operated to be released. That is, the degree of engagement between the flywheel 302 and the clutch disc 304 is reduced. As a result, the degree of power transmitted from engine 200 to transmission 400 decreases, and the input shaft speed of transmission 400 decreases.

  At time T (3), when the input shaft rotational speed becomes N (0), the rotational speed difference between the engine rotational speed and the rotational speed of the input shaft of the transmission 400 is equal to or greater than a predetermined value (1). Then, it is determined that the rotational speed is changing (YES in S104).

  At this time, if there is no change in the operation amount of clutch actuator 500 (NO in S108), a value obtained by adding a predetermined value to the operation amount of clutch actuator 500 detected by clutch stroke sensor 502 is set as the target value. Then, the clutch actuator 500 is controlled so as to reach the set target value (S112). Since the clutch 300 operates on the engagement side, the degree of engagement between the flywheel 302 and the clutch disk 304 increases, and the rotational speed of the input shaft of the transmission 400 increases.

  When the rotational speed difference between the engine rotational speed and the rotational speed of the input shaft of transmission 400 becomes smaller than a predetermined value (1) at time T (4) (NO in S116), clutch stroke sensor 502 The detected operation amount of the clutch actuator 500 is set as a target value (S118).

  After time T (4), the clutch 300 is engaged so that the clutch 300 is engaged when a predetermined condition for executing creep control is not satisfied, for example, when the driver starts to depress the brake pedal 150 or the accelerator pedal 152. The actuator 500 is controlled. When clutch 300 is engaged (YES in S120), the target value is returned to the initial value (S122).

  As described above, according to the control device for a vehicle according to the present embodiment, after the clutch actuator is controlled so that the clutch is in a predetermined half-engaged state, the hydraulic pressure caused by the volume expansion of the hydraulic oil. When the clutch is operating on the disengagement side due to an increase in the engine speed, even if there is no change in the operation amount of the clutch actuator, the speed difference between the engine and the input shaft speed of the transmission changes. . In such a case, by controlling the clutch actuator by setting the operation amount that has changed from the clutch actuator operation amount detected by the clutch stroke sensor to the clutch engagement side by a predetermined value as a target value. The clutch that has been operated to the disengagement side due to the volume expansion of the hydraulic oil can be brought into the semi-engaged state again. Therefore, creep running can be performed appropriately. Accordingly, it is possible to provide a vehicle control device, a control method, a program for realizing the method, and a recording medium recording the program for controlling the clutch with high accuracy during creep running.

  Further, when the clutch returns to the half-engaged state, the rotational speed difference becomes equal to or less than a predetermined value. Therefore, the clutch half-engaged state can be continued by maintaining the operation amount of the actuator. Therefore, creep running can be performed appropriately.

  Furthermore, since the generation of frictional heat is suppressed when the clutch is engaged or disengaged, the temperature of the hydraulic oil is lowered and the expanded volume is reduced. Therefore, if a predetermined condition is not satisfied, a predetermined operation amount corresponding to the half-engaged state is set as a target value, so that the predetermined condition is satisfied again and the clutch is in the half-engaged state. When the clutch actuator is controlled so that the clutch is controlled, the clutch can be brought into a semi-engaged state with high accuracy, so that creep travel can be appropriately performed.

  In the present embodiment, when the vehicle is creeping and the engine rotational speed and the clutch actuator operation amount do not vary and only the rotational speed of the input shaft of the transmission decreases, the clutch is engaged. The clutch actuator is controlled so that the clutch operates so that, for example, in addition to a decrease in the rotational speed of the input shaft of the transmission, when the engine blow-up (an increase in the engine rotational speed) is detected, the clutch is The clutch actuator may be controlled to operate on the engagement side. The engine blow-up may be determined based on, for example, the amount of change in the engine speed being equal to or greater than a predetermined value.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram which shows the structure of the vehicle by which the control apparatus which concerns on this Embodiment is mounted. It is a functional block diagram of ECU which is a control device of vehicles concerning this embodiment. It is a flowchart which shows the control structure of the program performed with ECU which is the control apparatus of the vehicle which concerns on this Embodiment. It is a timing chart which shows operation | movement of ECU which is a control apparatus of the vehicle which concerns on this Embodiment.

Explanation of symbols

  100 ECU, 102 Stop lamp switch, 104 Accelerator opening sensor, 106 Input shaft speed sensor, 108 Engine speed sensor, 150 Brake pedal, 152 Accel pedal, 200 Engine, 202 Crankshaft, 300 Clutch, 302 Flywheel, 304 Clutch disc, 306 Clutch cover, 308 output shaft, 400 transmission, 450 clutch release cylinder, 452 hydraulic circuit, 454 piston, 456 release shaft, 500 clutch actuator, 502 clutch stroke sensor, 600 input I / F, 700 arithmetic processing unit , 702 Condition establishment determination unit, 704 Rotational speed difference variation determination unit, 706 Position variation determination unit, 708 Target value setting unit, 710 Actuator control unit, 71 Engagement determination unit, 800 storage unit, 900 output I / F.

Claims (16)

An internal combustion engine, a clutch that is connected to an output shaft of the internal combustion engine and operates to connect / disconnect power transmission by hydraulic pressure, and a transmission that transmits the power from the internal combustion engine via the clutch are mounted. The clutch is operated by driving an actuator, and the actuator enters a predetermined half-engaged state when a predetermined condition is satisfied with respect to the state of the vehicle. Control is started and
The controller is
Means for detecting an actuation amount of the actuator;
Means for detecting the rotational speed of the internal combustion engine;
Means for detecting the rotational speed of the input shaft of the transmission;
After the actuator is controlled so that the clutch is in a predetermined half-engaged state, the rotational speed difference between the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission fluctuates. And a control means for controlling the actuator so that the clutch is operated to the engagement side when the detected operation amount does not change. The control means includes
Setting means for setting, as a target value, an operation amount that has changed from the detected operation amount to a clutch engagement side by a predetermined value;
The vehicle control device according to claim 1, further comprising means for controlling the actuator so that the detected operation amount becomes the set target value.   The setting means includes means for setting a once changed target value to a predetermined value corresponding to the half-engagement state when the predetermined condition is not satisfied. The vehicle control device described.   The control device according to any one of claims 1 to 3, further comprising means for holding an operation amount of the actuator when the rotation speed difference is not changed by the control of the actuator by the control means. Vehicle control device.   The predetermined condition includes a condition that the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission do not fluctuate, and a condition that the accelerator pedal and the brake pedal provided in the vehicle are released. The control apparatus of the vehicle in any one of Claims 1-4 containing these. The controller is
Means for determining that the rotational speed difference fluctuates if the detected rotational speed difference is greater than or equal to a predetermined first value;
The apparatus further includes means for determining that the detected operating amount is in a state in which the detected operating amount does not vary when the detected change amount of the operating amount is equal to or less than a predetermined second value. The vehicle control device according to claim 5. A clutch release cylinder is connected to the clutch via a hydraulic circuit,
The clutch release cylinder supplies hydraulic pressure to the clutch via a hydraulic circuit by moving a piston slidably provided therein by driving the actuator.
A reservoir for storing hydraulic oil supplied into the hydraulic circuit is connected to the clutch release cylinder via a reserve port,
The reserve port and the hydraulic circuit are in a disconnected state when the piston is in a position where the clutch is released from a position corresponding to the predetermined half-engaged state. The vehicle control apparatus according to claim 1. An internal combustion engine, a clutch that is connected to an output shaft of the internal combustion engine and operates to connect / disconnect power transmission by hydraulic pressure, and a transmission that transmits the power from the internal combustion engine via the clutch are mounted. The clutch is actuated by driving an actuator, and the actuator enters a predetermined half-engaged state when a predetermined condition for the state of the vehicle is satisfied. Controlled to be
The control method is:
Detecting an operation amount of the actuator;
Detecting the rotational speed of the internal combustion engine;
Detecting the rotational speed of the input shaft of the transmission;
After the actuator is controlled so that the clutch is in a predetermined half-engaged state, the rotational speed difference between the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission fluctuates. And a control step of controlling the actuator so that the clutch is operated to the engagement side when the detected operation amount does not change. The control step includes
A setting step of setting, as a target value, an operation amount that has changed from the detected operation amount to a clutch engagement side by a predetermined value;
The vehicle control method according to claim 8, further comprising: controlling the actuator so that the detected operation amount becomes the set target value.   The vehicle according to claim 9, wherein the setting step further includes a step of setting a predetermined operation amount corresponding to the half-engaged state as the target value when the predetermined condition is not satisfied. Control method.   The vehicle control method according to any one of claims 8 to 10, wherein the control method further includes a step of holding an operation amount of the actuator when the difference in the rotation speed is not changed by the control of the actuator in the control step. Control method.   The predetermined condition includes a condition that the rotational speed of the internal combustion engine and the rotational speed of the input shaft of the transmission do not fluctuate, and a condition that the accelerator pedal and the brake pedal provided in the vehicle are released. The vehicle control method according to claim 8, comprising: The control method is:
Determining that the rotational speed difference fluctuates if the detected rotational speed difference is greater than or equal to a predetermined first value;
The method further comprises the step of determining that the detected operating amount is in a state in which the detected operating amount does not vary when the detected change amount of the operating amount is equal to or less than a predetermined second value. The vehicle control method according to any one of the above. A clutch release cylinder is connected to the clutch via a hydraulic circuit,
The clutch release cylinder supplies hydraulic pressure to the clutch via a hydraulic circuit by moving a piston slidably provided therein by driving the actuator.
A reservoir for storing hydraulic oil supplied into the hydraulic circuit is connected to the clutch release cylinder via a reserve port,
The reserve port and the hydraulic circuit are in a shut-off state when the piston is in a position where the clutch is released from a position corresponding to the predetermined half-engaged state. A vehicle control method according to claim 1.   The program which implement | achieves the control method of the vehicle in any one of Claims 8-14 with a computer.   The recording medium which recorded the program which implement | achieves the control method of the vehicle in any one of Claims 8-14 with a computer.

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